1. Field of the Invention
The invention relates to a discharge device for discharging the contents of a container containing a viscous substance, the shell material of which container is elastic, which discharge device has a cylindrical winding roller and counter pressure roller, and an arrangement for pressing said rollers against each other, and a method for emptying a container with an elastic shell material.
2. Description of the Related Art
Industry often uses high viscosity substances, such as for example glues or sealing pastes or the like, which are administered to a use target. Due to the viscosity, aids are needed for emptying the substance from its container. One known manner to store and transport these substances to the use location are fixed-structure drum containers, from which the emptying occurs as aided by a conveying lid, i.e. the loose lid of the container is pressed into the container, whereby the content of the container is discharged. A problem with these is the relatively small size of the package, for example a barrel, whereby the container must often be changed, or if the package size is increased the emptying apparatus becomes impractically large and expensive. Additionally when changing the container, air and impurities may end up in the substance to be used, which may have an adverse effect on the substance properties. Additionally air, which has ended up in the system, may impede administration of the substance, which administration should be even and according to desire.
Said substances can be transported and stored also in sack-like containers, the shell of which is elastic. The emptying of these, especially as the size of the sack and the amount of substance it contains increase, is difficult, and situations may arise, where the flow speed of the substance emerging from the container varies, which makes its use difficult. Additionally substance is easily left inside these containers, i.e. the portion going to waste may be significant. Further it is difficult to keep the amount of discharged substance standard.
Patent publication US 2010/0006594 shows an apparatus for emptying an elastic sack-like container. The described apparatus comprises two rollers, which can be pressed against each other and the sack is pulled between them. The rollers move downward and simultaneously push out the content of the sack. The publication mentions that the rollers rotate by themselves or they have been equipped with a motor, which rotates them. The publication mentions that this can only increase the speed at which the content is removed. The outlet additionally has a pump, with which the outlet flow can according to the publication be further increased. This does however not strive for evenness of the outlet flow. This further requires an arrangement, which lifts the sack past the rollers. A forklift or a corresponding work machine is suggested as such. Work safety aspects must thus also be taken into account.
Patent publication U.S. Pat. No. 4,627,551 shows a device for emptying a sack containing a paste-like material. This has two adjacent rollers, both of which are rotated, and the sack to be emptied is fed between the rollers. The rollers are rotated with a hand crank and the movement of the rollers pushes the emptied sack upwards between them. The publication also mentions that the rollers are arranged so that friction keeps the sack in place if the emptying is stopped for a while. Such a method is in practice impossible to apply to a larger scale than a traditional sack. Attention has also not been paid to the evenness of the emptying.